Eye Diseases Commons^™

Cannabinoids And Retinal Fibrotic Disorders., Lucy June Sloan

Electronic Theses and Dissertations

Retinal fibrosis is detrimental to vision. Retinal pigment epithelial (RPE) cells contribute to several retinal fibrotic diseases. Upon exposure to TGF-β, a key fibrotic cytokine, RPE cells trans-differentiate to myofibroblasts marked by the integration of α-SMA fibers into F-actin stress fibers, which confer strong contractility. Myofibroblasts produce and contract the collagen-rich fibrotic scar and disrupt retinal architecture. In this study, we investigated the in vitro effects of the putative endocannabinoid compound N-oleoyl dopamine (OLDA) on TGF-β2 induced porcine RPE cell contraction and α-SMA expression. Using an in vitro collagen matrix contraction assay, we found that OLDA inhibited TGF-β2 induced contraction …

Secretogranin Iii Stringently Regulates Pathological But Not Physiological Angiogenesis In Oxygen-Induced Retinopathy, Chang Dai, Prabuddha Waduge, Liyang Ji, Chengchi Huang, Ye He, Hong Tian, Elizabeth Zuniga-Sanchez, Amit Bhatt, Iok-Hou Pang, Guanfang Su, Keith A Webster, Wei Li

Faculty, Staff and Students Publications

Conventional angiogenic factors, such as vascular endothelial growth factor (VEGF), regulate both pathological and physiological angiogenesis indiscriminately, and their inhibitors may elicit adverse side effects. Secretogranin III (Scg3) was recently reported to be a diabetes-restricted VEGF-independent angiogenic factor, but the disease selectivity of Scg3 in retinopathy of prematurity (ROP), a retinal disease in preterm infants with concurrent pathological and physiological angiogenesis, was not defined. Here, using oxygen-induced retinopathy (OIR) mice, a surrogate model of ROP, we quantified an exclusive binding of Scg3 to diseased versus healthy developing neovessels that contrasted sharply with the ubiquitous binding of VEGF. Functional immunohistochemistry visualized …

Review Of Evidence For Environmental Causes Of Uveal Coloboma, Evan B Selzer, Delphine Blain, Robert B Hufnagel, Philip J Lupo, Laura E Mitchell, Brian P Brooks

Faculty, Staff and Student Publications

Uveal coloboma is a condition defined by missing ocular tissues and is a significant cause of childhood blindness. It occurs from a failure of the optic fissure to close during embryonic development and may lead to missing parts of the iris, ciliary body, retina, choroid, and optic nerve. Because there is no treatment for coloboma, efforts have focused on prevention. While several genetic causes of coloboma have been identified, little definitive research exists regarding the environmental causes of this condition. We review the current literature on environmental factors associated with coloboma in an effort to guide future research and preventative …

Effect Of Glaucoma On Melanopsin Retinal Ganglion Cells In Mice, Abigail Mcmullen

Williams Honors College, Honors Research Projects

Within the mammalian retina, there are melanopsin-containing ganglion cells. These intrinsically photoreceptive cells help control behavioral aspects of vision as well as to aid in circadian rhythms. In this project, it will be determined whether or not glaucoma has an effect on these cells, and what that effect is, from different points in the disease. Glaucoma is an eye disease that damages the retinal ganglion cells and eventually causes them to die, also it can be linked to irregular circadian rhythm. Many techniques will be used to prepare this project but computer imaging will be the primary method for determining …

Glaucoma Alters The Morphology Of Mouse Melanopsin-Containing Retinal Ganglion Cells, Kristin Keenan

Williams Honors College, Honors Research Projects

Melanopsin ganglion cells are intrinsically photosensitive ganglion cells in the mammalian retina. These cells mediate aspects of non-image forming vision to help regular circadian rhythm. Glaucoma is an eye disease involving an increase in intraocular pressure that has been linked to irregular circadian rhythm. This project will investigate the impact glaucoma has on these melanopsin ganglion cells at different pathological timepoints. This will be performed by using dissection, immunohistochemistry, and computer imaging methods to visualize, trace, and measure the cells’ morphologies in both control and glaucomatous retinas at different timepoints of disease to analyze if glaucoma has a significant effect …

Gut Microbiota From Sjögren Syndrome Patients Causes Decreased T Regulatory Cells In The Lymphoid Organs And Desiccation-Induced Corneal Barrier Disruption In Mice, Laura Schaefer, Claudia M Trujillo-Vargas, Firas S Midani, Stephen C Pflugfelder, Robert A Britton, Cintia S De Paiva

Faculty, Staff and Students Publications

Sjögren syndrome (SS) is an autoimmune inflammatory disorder characterized by secretory dysfunction in the eye and mouth; in the eye, this results in tear film instability, reduced tear production, and corneal barrier disruption. A growing number of studies show that homeostasis of the ocular surface is impacted by the intestinal microbiome, and several 16S sequencing studies have demonstrated dysbiosis of the intestinal microbiota in SS patients. In this study, we utilized metagenomic sequencing to perform a deeper analysis of the intestinal microbiome using stools collected from sex- and age-matched healthy (n = 20), dry eye (n = 4) …

Role Of Meibum And Tear Phospholipids In The Evaporative Water Loss Associated With Dry Eye., Samiyyah M. Sledge

Electronic Theses and Dissertations

It is generally believed that the tear film lipid surface film inhibits the rate of evaporation (Revap) of the underlying tear aqueous. It is also generally believed that changes in the composition of the tear film lipid layer is responsible for an increase in Revap in patients with dry eye. Both of these ideas have never been proven. The purpose of the current studies was to test these ideas. Revap was measured in vitro gravimetrically. Lipid spreading was measured using Raman spectroscopy and microscopy. The influence of the following surface films on the Revap of the sub phase of physiologically …

Super-Resolution Microscopy Reveals Photoreceptor-Specific Subciliary Location And Function Of Ciliopathy-Associated Protein Cep290, Valencia L Potter, Abigail R Moye, Michael A Robichaux, Theodore G Wensel

Faculty, Staff and Students Publications

Mutations in the cilium-associated protein CEP290 cause retinal degeneration as part of multiorgan ciliopathies or as retina-specific diseases. The precise location and the functional roles of CEP290 within cilia and, specifically, the connecting cilia (CC) of photoreceptors, remain unclear. We used super-resolution fluorescence microscopy and electron microscopy to localize CEP290 in the CC and in the primary cilia of cultured cells with subdiffraction resolution and to determine effects of CEP290 deficiency in 3 mutant models. Radially, CEP290 localizes in close proximity to the microtubule doublets in the region between the doublets and the ciliary membrane. Longitudinally, it is distributed throughout …

Structure And Dynamics Of Photoreceptor Sensory Cilia, Theodore G Wensel, Valencia L Potter, Abigail Moye, Zhixian Zhang, Michael A Robichaux

Faculty, Staff and Students Publications

The rod and cone photoreceptor cells of the vertebrate retina have highly specialized structures that enable them to carry out their function of light detection over a broad range of illumination intensities with optimized spatial and temporal resolution. Most prominent are their unusually large sensory cilia, consisting of outer segments packed with photosensitive disc membranes, a connecting cilium with many features reminiscent of the primary cilium transition zone, and a pair of centrioles forming a basal body which serves as the platform upon which the ciliary axoneme is assembled. These structures form a highway through which an enormous flux of …

Neurovascular Regulation In Diabetic Retinopathy And Emerging Therapies, Liyang Ji, Hong Tian, Keith A Webster, Wei Li

Faculty, Staff and Students Publications

Diabetic retinopathy (DR) is the leading cause of vision loss in working adults in developed countries. The disease traditionally classified as a microvascular complication of diabetes is now widely recognized as a neurovascular disorder resulting from disruption of the retinal neurovascular unit (NVU). The NVU comprising retinal neurons, glia and vascular cells coordinately regulates blood flow, vascular density and permeability to maintain homeostasis. Disturbance of the NVU during DR can lead to vision-threatening clinical manifestations. A limited number of signaling pathways have been identified for intercellular communication within the NVU, including vascular endothelial growth factor (VEGF), the master switch for …

Retinal Regeneration In A Genetic Mouse Model Of Glaucoma, Joshua Paris

Masters Theses

Glaucoma is a degenerative retinal disease characterized by progressive loss of retinal ganglion cells (RGCs). Previous studies have shown that application of a specific α7 nicotinic acetylcholine receptor agonist, PNU-282987 (PNU), onto the murine retina induces neurogenesis of numerous retinal cell types, including RGCs. The aim of this study is to characterize the short-term and long-term effects of PNU in a glaucoma model. The effects of PNU were analyzed in a DBA/2J mouse model that auto-induces a glaucoma-like condition in adulthood. These mice manifest an elevated intraocular pressure (IOP) starting at 6 months, followed by loss of RGCs. To assess …

Search For Palladin, An Actin-Associated Protein, In Pig Retinal Pigmented Epithelium And Its Role In Epithelial-Mesenchymal Transition, Katrina Powell

Undergraduate Theses

This study investigates the expression of Palladin, a phosphoprotein product of the PALLD gene, in the retinal pigmented epithelium (RPE). Palladin is an actin cross-linking protein and plays a role in cell adhesion and motility. Published reports have demonstrated that a down regulation of Palladin in colon cancer cells results in a reorganization of the actin cytoskeleton, causing the cells to lose their typical shape, become proliferative and migratory. This process is otherwise known as epithelial-mesenchymal transition (EMT). A similar EMT phenomenon is observed when the RPE is exposed to the vitreous humor in patients with proliferative vitreoretinopathy (PVR). In …

Pathogenesis Of Dry Eye In Graft Versus Host Disease (Gvhd): Role Of Ocular Mucins And Conjunctival Fibrosis, Kiumars Shamloo

Pharmaceutical Sciences (PhD) Dissertations

Allogenic hematopoietic stem cell transplantation is a procedure that offers a possible cure for hematologic cancers and other hematologic disorders. Unfortunately, despite the increasing survival rate of patients, the quality of their life is adversely affected by the allogeneic bone marrow transplantation’s major side effect i.e Graft vs. Host Disease (GVHD). GVHD is a complex, multi-organ disease resulting from an immunological attack by donor engrafted immune cells to host organs, including the eye surface. Mostly based on the time of disease onset after transplantation, GVHD is divided into the acute and chronic phase. The eyes may be involved in both …

Single-Cell Transcriptomics Identifies Limbal Stem Cell Population And Cell Types Mapping Its Differentiation Trajectory In Limbal Basal Epithelium Of Human Cornea, De-Quan Li, Sangbae Kim, Jin-Miao Li, Qianmiao Gao, Jongsu Choi, Fang Bian, Jiaoyue Hu, Yun Zhang, Jin Li, Rong Lu, Yumei Li, Stephen C Pflugfelder, Hongyu Miao, Rui Chen

Faculty, Staff and Students Publications

PURPOSE: This study aimed to uncover novel cell types in heterogenous basal limbus of human cornea for identifying LSC at single cell resolution.

METHODS: Single cells of human limbal basal epithelium were isolated from young donor corneas. Single-cell RNA-Sequencing was performed using 10x Genomics platform, followed by clustering cell types through the graph-based visualization method UMAP and unbiased computational informatic analysis. Tissue RNA in situ hybridization with RNAscope, immunofluorescent staining and multiple functional assays were performed using human corneas and limbal epithelial culture models.

RESULTS: Single-cell transcriptomics of 16,360 limbal basal cells revealed 12 cell clusters belonging to three lineages. …

Serial Block-Face Scanning Electron Microscopy (Sbf-Sem) Of Biological Tissue Samples, Justin A Courson, Paul T Landry, Thao Do, Eric Spehlmann, Pascal J Lafontant, Nimesh Patel, Rolando E Rumbaut, Alan R Burns

Faculty, Staff and Students Publications

Serial block-face scanning electron microscopy (SBF-SEM) allows for the collection of hundreds to thousands of serially-registered ultrastructural images, offering an unprecedented three-dimensional view of tissue microanatomy. While SBF-SEM has seen an exponential increase in use in recent years, technical aspects such as proper tissue preparation and imaging parameters are paramount for the success of this imaging modality. This imaging system benefits from the automated nature of the device, allowing one to leave the microscope unattended during the imaging process, with the automated collection of hundreds of images possible in a single day. However, without appropriate tissue preparation cellular ultrastructure can …

Development Of Light Actuated Chemical Delivery Platform On A 2-D Array Of Micropore Structure, Hojjat Rostami Azmand, Hojjat Rostami Azmand

Dissertations and Theses

Localized chemical delivery plays an essential role in the fundamental information transfers within biological systems. Thus, the ability to mimic the natural chemical signal modulation would provide significant contributions to understand the functional signaling pathway of biological cells and develop new prosthetic devices for neurological disorders. In this paper, we demonstrate a light-controlled hydrogel platform that can be used for localized chemical delivery in a high spatial resolution. By utilizing the photothermal behavior of graphene-hydrogel composites confined within micron-sized fluidic channels, patterned light illumination creates the parallel and independent actuation of chemical release in a group of fluidic ports. The …

From Inner Segment To Outer Segment: Palmitoylation Of Photoreceptor Na+, K+-Atpase And The Importance Of Prcd In Photoreceptor Outer Segment Morphogenesis, Emily R. Sechrest

Graduate Theses, Dissertations, and Problem Reports (ETD)

Photoreceptors are specialized neuroepithelial cells which are optimized for efficient capture of light and initiation of visual transduction. These cells have several compartments which are very important for proper visual function and segregation of cellular processes, including the outer segment (OS), inner segment (IS), nucleus, and synapse. The IS houses all of the cellular organelles and biosynthetic molecular machinery the cell requires and is the site of protein synthesis. The light-sensing OS is a highly modified, primary cilium, which contains many stacks of double membranous discs which house proteins required for formation and maintenance of OS structure, as well as …

Extracellular Vesicles Released By Human Retinal Pigment Epithelium Mediate Increased Polarised Secretion Of Drusen Proteins In Response To Amd Stressors, Miguel Flores-Bellver, Jason Mighty, Silvia Aparicio-Domingo, Kang V. Li, Cui Shi, Jing Zhou, Hannah Cobb, Patrick Mcgrath, German Michelis, Patricia Lenhart, Ganna Bilousova, Søren Heissel, Michael J. Rudy, Christina Coughlan, Andrew E. Goodspeed, S. Patricia Becerra, Stephen Redenti, M. Valeria Canto-Soler

Publications and Research

Age-related macular degeneration (AMD) is a leading cause of blindness worldwide. Drusen are key contributors to the etiology of AMD and the ability to modulate drusen biogenesis could lead to therapeutic strategies to slow or halt AMD progression. The mechanisms underlying drusen biogenesis, however, remain mostly unknown. Here we demonstrate that under homeostatic conditions extracellular vesicles (EVs) secreted by retinal pigment epithelium (RPE) cells are enriched in proteins associated with mechanisms involved in AMD pathophysiology, including oxidative stress, immune response, inflammation, complement system and drusen composition. Furthermore, we provide first evidence that drusen-associated proteins are released as cargo of extracellular …

Qki-Mediated Cholesterol Biosynthesis In Eye Lens And Myelin Of The Central Nervous System, Seula Shin, Seula Shin

Dissertations and Theses (Open Access)

Cells obtain cholesterol in two ways, de novo biosynthesis and uptake from circulation. While most tissues utilize both sources, eye lens and brain depend extensively on cholesterol biosynthesis due to the limited supply from circulation. Lens cell membrane consists of highest portion of cholesterol. Brain is the most cholesterol-rich organ, which accounts for 23% of total cholesterol. Genetic mutations of cholesterol biosynthesis enzymes in humans and animal models present cataracts and hypomyelinating disorders linked to neurological impairment. Yet, it remains unclear how gene expression of cholesterol biosynthesis is regulated in lens and brain. Therefore, studying cholesterol biosynthesis in both tissues …

Qki-Mediated Cholesterol Biosynthesis In Eye Lens And Myelin Of The Central Nervous System, Seula Shin, Seula Shin

Dissertations and Theses (Open Access)

Cells obtain cholesterol in two ways, de novo biosynthesis and uptake from circulation. While most tissues utilize both sources, eye lens and brain depend extensively on cholesterol biosynthesis due to the limited supply from circulation. Lens cell membrane consists of highest portion of cholesterol. Brain is the most cholesterol-rich organ, which accounts for 23% of total cholesterol. Genetic mutations of cholesterol biosynthesis enzymes in humans and animal models present cataracts and hypomyelinating disorders linked to neurological impairment. Yet, it remains unclear how gene expression of cholesterol biosynthesis is regulated in lens and brain. Therefore, studying cholesterol biosynthesis in both tissues …

Loss Of Class Iii Phosphoinositide 3-Kinase Vps34 Results In Cone Degeneration, Ammaji Rajala, Feng He, Robert E Anderson, Theodore G Wensel, Raju V S Rajala

Faculty, Staff and Students Publications

The major pathway for the production of the low-abundance membrane lipid phosphatidylinositol 3-phosphate (PI(3)P) synthesis is catalyzed by class III phosphoinositide 3-kinase (PI3K) Vps34. The absence of Vps34 was previously found to disrupt autophagy and other membrane-trafficking pathways in some sensory neurons, but the roles of phosphatidylinositol 3-phosphate and Vps34 in cone photoreceptor cells have not previously been explored. We found that the deletion of Vps34 in neighboring rods in mouse retina did not disrupt cone function up to 8 weeks after birth, despite diminished rod function. Immunoblotting and lipid analysis of cones isolated from the cone-dominant retinas of the …

Mtor-Initiated Metabolic Switch And Degeneration In The Retinal Pigment Epithelium, Young-Mi Go, Jing Zhang, Jolyn Fernandes, Christopher Litwin, Rui Chen, Theodore G Wensel, Dean P Jones, Jiyang Cai, Yan Chen

Faculty, Staff and Students Publications

The retinal pigment epithelium (RPE) is a particularly vulnerable tissue to age-dependent degeneration. Over the life span, the RPE develops an expanded endo-lysosomal compartment to maintain the high efficiency of phagocytosis and degradation of photoreceptor outer segments (POS) necessary for photoreceptor survival. As the assembly and activation of the mechanistic target of rapamycin complex 1 (mTORC1) occur on the lysosome surface, increased lysosome mass with aging leads to higher mTORC1 activity. The functional consequences of hyperactive mTORC1 in the RPE are unclear. In the current study, we used integrated high-resolution metabolomic and genomic approaches to examine mice with RPE-specific deletion …

Parameter Estimation For Tear Film Thinning, Rayanne Luke

Biology and Medicine Through Mathematics Conference

No abstract provided.

Investigating The Morphology Of Iprgcs In Control Vs. Glaucomatous Retinas, Samantha Cook

Williams Honors College, Honors Research Projects

Glaucoma is a build-up of pressure in the eye that leads to the gradual loss of sight. The intention of this study was to investigate how glaucoma affects intrinsically photosensitive Retinal Ganglion Cells (ipRGCs). These cells contain melanopsin, a photopigment, that enables the cells to react to light. Four-month-old control and five-month-old glaucoma mice retinas were dissected, stained using primary and secondary antibodies, then traced using ImageJ’s Simple Neurite Tracer. There were no significant differences in soma size, total dendritic length, dendritic field size, and dendritic field diameter between control and glaucoma ipRGCs. However, further research is needed to provide …

Role Of Ciliary Proteins Adp Ribosylation Factor Like Gtpase 13b (Arl13b) And Bardet-Biedl Syndrome-8 (Bbs8) In Photoreceptor Outer Segment Morphogenesis, Maintenance, And Viability, Tanya L. Dilan

Graduate Theses, Dissertations, and Problem Reports (ETD)

Photoreceptor neurons are modified primary cilia with an extended ciliary compartment known as the outer segment (OS). The mechanisms behind the elaboration of photoreceptor cilia, OS morphogenesis, and maintenance remain poorly understood. In this work, we focused on dissecting the role of two ciliary proteins, the small GTPase ADP-ribosylation factor-like GTPase 13B (ARL13B) and Bardet-Biedl Syndrome-8 (BBS8) in the context of photoreceptor biology. Both BBS8 and ARL13B are linked to defects in ciliogenesis (cilia development) and Retinitis Pigmentosa (vision loss). ARL13B is implicated in regulating ciliary length, and BBS8 is part of the Bardet-Biedl Syndrome complex (BBSome); the BBSome is …

Characterization Of Extracellular Vesicles From Human Diabetic Retinopathy Retinal Tissue In Vitro And From Urine Of Human Patients With Diabetic Retinopathy, Jason Mighty

Dissertations, Theses, and Capstone Projects

Diabetic Retinopathy (DR) is a neurovascular complication associated with diabetes mellitus that affects approximately 120 million people worldwide and its prevalence is expected to reach 190 million by 2030. DR diagnosis is accomplished with fundus ophthalmoscopy often when retinal damage and vision loss have already occurred. A group of biomarker being explored for early detection of diseases are extracellular vesicles (EVs), which are nanometer diameter lipid enclosed vesicles, released from all cell types and containing genetic cargo reflective of releasing cell state. EV biomarkers are currently being explored to help monitor disease predisposition, pathogenesis and response to treatment. While an …

Eye Tissue Regeneration: Seam As A Cure For Prevalent Eye Disease, Molly Bute

Biology: Student Scholarship & Creative Works

SEAM (Self-formed ectodermal autonomous multizone) is a form of eye tissue regeneration discovered by Japanese scientists in 2016. This tissue regeneration encompasses tissues from all areas of the human eye. The SEAM forms tissues using stem cells, induced pluripotent stem cells were used in the first study, and produces four concentric zones. The SEAM that has been created was shown to cure corneal blindness in animal models, and has the potential to cure a multitude of human eye diseases in the future.

An Active Efficient Coding Model Of The Development Of Amblyopia, Samuel Eckmann, Lukas Klimmasch, Bertram Shi, Jochen Triesch

MODVIS Workshop

No abstract provided.

Functional And Structural Impact Of The Loss Of The Leucine-Rich Repeat Protein Lrit1 In The Mouse Retina., Catherine Ann Cobb

Electronic Theses and Dissertations

Mutations in genes encoding the leucine-rich repeat (LRR) proteins nyctalopin and LRIT3 lead to complete congenital stationary night blindness because they are critical to depolarizing bipolar cell function in the retina. LRIT3 has two closely related family members, LRIT1 and LRIT2. In silico analyses of publicly available RNA-Seq data showed that Lrit1 was highly expressed in the retina. Here I describe the expression pattern and impact of loss of LRIT1 on retinal function. To enable these studies, we used CRISPR/Cas9 technology to create an Lrit1^-/- mouse line. Retinal morphology and morphometry analyses showed no gross changes in retinal structure …

Reduced Intraepithelial Corneal Nerve Density And Sensitivity Accompany Desiccating Stress And Aging In C57bl/6 Mice, Mary Ann Stepp, Sonali Pal-Ghosh, Gauri Tadvalkar, Alexa Williams, S Pflugfelder, C De Paiva

Anatomy and Regenerative Biology Faculty Publications

Dry Eye disease causes discomfort and pain in millions of patients. Using a mouse acute desiccating stress (DS) model we show that DS induces a reduction in intraepithelial corneal nerve (ICN) density, corneal sensitivity, and apical extension of the intraepithelial nerve terminals (INTs) that branch from the subbasal nerves (SBNs). Topical application of 0.02% Mitomycin C (MMC) or vehicle alone has no impact on the overall loss of axon density due to acute DS. Chronic dry eye, which develops progressively as C57BL/6 mice age, is accompanied by significant loss of the ICNs and corneal sensitivity between 2 and 24 months …